1. Field of the Invention
The present invention relates to an in-vehicle apparatus having a handsfree function, and more particularly to an in-vehicle apparatus that is capable of establishing connections to multiple cellular phones at the same time using a handsfree communication protocol for handsfree communication.
2. Description of Related Art
There is known an in-vehicle handsfree apparatus supporting a Bluetooth (registered trademark, referred to also as BT) communication function. According to a known configuration, when a cellular phone supporting a BT communication function is carried into a compartment of a vehicle equipped with the in-vehicle handsfree apparatus, the cellular phone and the in-vehicle handsfree apparatus become communicable with each other via a BT communication link and are connected with each other using a handsfree profile (HFP) defined in BT communications standards for handsfree communications. JP-2003-218996A discloses a configuration for establishing connections (so called multi-connections) between an in-vehicle handsfree apparatus and multiple cellular phones at the same time using the HFP.
When the in-vehicle handsfree apparatus is connected with multiple cellular phones at the same time using HFP, a possible situation is that a first cellular phone of the multiple cellular phones receives an incoming call while a second cellular phone of the multiple cellular phones is in a handsfree communicating state. Taking into consideration the above situation, the assignee company of the present application had filed the patent application JP-2009-224984A (corresponding to US-2009-0209297A) to disclose a method of putting the second cellular phone being in the handsfree communicating state on hold and then switching the first cellular phone receiving the incoming call into the handsfree communicating state.
When an in-vehicle handsfree apparatus is connected with multiple cellular phones using HFP, a user can perform communications in a handsfree communicating state or a handset communicating state. In the handsfree communicating state, the user performs the communications using a microphone and a speaker of the in-vehicle handsfree apparatus. In the handset communicating state, the user performs the communications using a microphone and a speaker of the cellular phone. The inventor of the present application considers that a user may select the handsfree communicating state when the user does not take care of a passenger listening to content of the call, and a user may select the handset communicating state when the user would like a passenger not to listen to content of the call.
Although JP-2009-224984A (corresponding to US-2009-0209297A) addresses a situation where a first cellular phone receives an incoming call while a second cellular phone is in a handsfree communicating state, JP-2009-224984A (corresponding to US-2009-0209297A) addresses nothing about a situation where a first cellular phone receives an incoming call while a second cellular phone is in a handset communicating state. The inventor of the present application considers that it is necessary to provide a way for a user to properly deal with a situation in which: multiple cellular phones are connected with the in-vehicle handsfree apparatus at the same; and a first cellular phone of the multiple cellular phones receives an incoming call while a second cellular phone of the multiple cellular phones is in a handset communicating state. The inventor of the present application further considers that, although one way to deal with the above-described situation is to allow a user to manipulate both of the first cellular phone receiving an incoming call and the second cellular hone in a handset communicating state, this way may not be appropriate because user operation becomes complicated.